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Current time:0:00Total duration:6:16

Video transcript

ok so now we're going to connect the negative side of our battery to our switches so we took a white wire and stripped about 3/4 of an inch of the insulation off of that wire we're going to bend it and loop it through the center terminal in one of our switches our single-pole double-throw switches and we chose a white wire here because it stands out against the black double-a battery housing makes it a little easier to see you can use really any color wire you want as long as it's you know copper or aluminum or something conducted okay so we're just crimping that wire against that terminal that comes out of our single-pole double-throw switch and the wire sticking straight up and that's going to make it easier to connect to so now we're trimming off the the back end of the wire and I actually trimmed it a little shorter than I probably should have so I would make the wire stick out a about half an inch past the double double-a battery housing there at the end now we're going to connect the two terminals of our switches the two Center terminals of our switches together so in order to do this we need to take about a half inch of insulation off of two sides of our remaining white wire and we're going to thread those wires again through the terminal blocks and so this wire is going through the center terminal block on the opposite switch of the that we've put in we're going to also strip the other end of the wire here off to make it easier to connect to the other side so this is basically allowing us to provide a way to connect the negative side of our battery to our switches and these switches basically allow us to reverse the polarity of the motors causing the bot to back up so they're a very simple way of hardware programming the bot okay so we're just running our wire through there and we want to loop it up and again we're going to take our needle nose pliers and we're going to crimp that wire tightly in place so that we have a good firm electrical connection and it's really important that those connections are very tight because the since we're not using solder the it's the what electricity won't flow if those connections aren't tight and so the bot won't perform like it's supposed to so that wire is just a little bit long so what I'm going to do is I'm going to provide I'm going to take it and this one's come loose just a little bit here so I'm going to crimp it down again on the other the other switch and then the wire that we just attached it's a little bit long so I'm going to instead of cutting it shorter since I've already stripped it I'm just going to loop it around and then I'm going to twist it against that exposed wire just like what we did with the LEDs and the resistors twisting those two wires together and that will allow us to have a good connection and spread the negative side of our battery to our switches so we've got our negative black wire here and we're going to trim it and then we're going to strip it again will strip probably about 1/2 to 3/4 of an inch of wire exposed is good a little bit it's always always good to have a little bit extra wire there in case you know you won't just want to make sure that it's not too short so again this is this is this one's kind of tricky to strip because the insulation is very soft and so you kind of have to really work with it but you don't want to pull too hard or you'll again damage those strands and this is a stranded wire as opposed to a solid wire so we're going to take those strands and we are going to wrap them around our twisted together wires and that's going to allow us to connect the negative side of our battery to our switches and begin to build the rest of the circuit that we need to make the bot work ok so now we're going to twist the wires together and it's kind of tricky because the stranded wire tends to spread out all over so you kind of have to work with it a little bit and it's really important to keep all those stranded wires against the other two solid core wires because if you have a stray wire sticking out somewhere it could cause a short or make a make a bad connection so we're just again twisting the wires together and to do that really we want to use our needle nose pliers and we're getting trying to get them as close together as possible in order to kind of trap those stranded wires we're going to take a piece of a little piece of aluminum foil and we'll wrap it around the the wires like we did for the LEDs that just helps to prevent the stranded wire from sticking out some where it shouldn't and also conducts helps to conduct the electricity sometimes it's hard to get the aluminum foil to stick to the the switches but you can do it or I should say stick to the the wires there and then again to hold everything together and insulate it we're going to take a small piece of electrical tape about a half an inch long and we're just going to wrap it around that and squeeze it very tightly to make sure that we've got a good connection again this is all about having really tight connections so what we're going to do is before we finish anything else we're going or before we glue anything else in place we're going to test to make sure that we're getting power that flows so now that we have our LED connected the switch does work so that indicates that yes the negative wire has is working and so we'll try the other one too yeah so we do have power flowing through that part of the circuit so now what we can do is we can hot glue our negative side of the battery in place make sure to disconnect the resistors before you do that so we're just going to take a little bit of hot glue here and again it's about half of us half the size of a dime a blob just enough to connect to cover over the connector and we want to make sure that the hot glue flows completely around the wire and that will help to hold it in place so that as we run our bot it stays and doesn't pop out so now we're ready for the next step